Generally, the keyboards on which Arabic letters are arrayed in QWERTY type are used to input various Arabic letters or alphabets on the PC. But, as the key pad areas are restricted in case of the smart phone or TV remote controller, plural Arabic letters should be assigned on each key button of the key pad and Arabic letter should be selected sequentially by the touching number of key buttons, which is rather troublesome as touching or operating number of key buttons is increased. If we distribute the keys in QWERTY array or if we increase the number of key to evade the above problems, the size of key buttons should be smaller and it will be more difficult to touch of the correct key buttons.
Various attempts have been tried to reduce the number of key operating without increasing the number of the key. FIG. 1 shows the conventional key pad for Arabic letters of one of the above attempt. Referring to FIG. 1, Arabic letters are assigned on the keys in such a way that 9 main letter keys 100 and plural derived letter keys 200 derived from the corresponding main letters are assigned on the key pad, and if any one of the main letters 100 is touched, then the corresponding plural derived letters 200 are shown on the keys adjacent to that main letter key 100, and if any one of the derived letter keys 200 is touched, then that derived letter is selected and inputted.
But the above key pad for Arabic letters has problem that the key location of the derived letters are changed depending on the selected main letters, so that the user may be confused about the key location of the derived letters, so it is difficult for the user to get accustomed to the letter layout of the key pads, which may result in frequent inputting errors or extended input time.